From: James Clarke <jrtc27@jrtc27.com>
Date: Thu, 7 Dec 2017 20:32:44 +0000
Subject: powerpc/lib/sstep: Fix building for powerpcspe
Origin: https://people.debian.org/~jrtc27/linux-ppc32/0001-powerpc-lib-sstep-Fix-building-for-powerpcspe.patch

On powerpcspe, ptesync is not a recognised instruction and so fails to
assemble. We don't expect to have to emulate an lwsync or a ptesync on a
32-bit kernel, so just ifdef them out, and catch any unexpected barrier
types.

Fixes: 3cdfcbfd32b9 ("powerpc: Change analyse_instr so it doesn't modify *regs")
Signed-off-by: James Clarke <jrtc27@jrtc27.com>
---
 arch/powerpc/lib/sstep.c | 4 ++++
 1 file changed, 4 insertions(+)

--- a/arch/powerpc/lib/sstep.c
+++ b/arch/powerpc/lib/sstep.c
@@ -2671,12 +2671,16 @@ void emulate_update_regs(struct pt_regs
 		case BARRIER_EIEIO:
 			eieio();
 			break;
+#ifdef __powerpc64__
 		case BARRIER_LWSYNC:
 			asm volatile("lwsync" : : : "memory");
 			break;
 		case BARRIER_PTESYNC:
 			asm volatile("ptesync" : : : "memory");
 			break;
+#endif
+		default:
+			WARN_ON_ONCE(1);
 		}
 		break;